Can you specify your hair type? i.e colour, thickness, length, texture, curly or straight?
Generally I would recommend using gel or wax to achieve a more mature look. Slicking your hair back with gel is a very sophisticated look if done properly. For this to work, your hair needs to have a decent length at the front/top - sides aren't as important. This will work if your hair is straight / thin.
If your hair is curly then you should definitely grow it out, and once its grown out, apply mousse to it.
I can't help much more until I know your specific hair type, but just remember that most sophisticated hairstyles, in males, consist of the wet-look (however you don't want to have greasy hair, so don't try to apply oils or serums to achieve the wet-look).
Slicked back hair / quiffs (which can be achieved with wax - a softer, less stiffening version of gel) are what you should be aiming for.
With curls, you want to grow them out and mousse them - this would look better with facial hair.
If you have afro hair, then obviously these styles won't work, so just let me know the specifics of your hair if I haven't already covered your hair type.